Here's another article, LA Times with more details.

http://www.latimes.com/news/nationworld/nation/la-na-hikers12-2008jun12,0,5906441.story

It sounds like the sequence of events was 50 mph winds, then snow, then whiteout, within minutes on the descent. I think its a situation where if you haven't been there you can't quite get it. I've been to 10,000 feet, I've been to Camp Muir, I've been in high winds, I've been in a whiteout, but never at the same time. I can imagine the disorentation, sorta. As the climbing instructor says, people have died just outside the doors at Camp Muir and never knew it.

The Rainier weather I can vouch for though. Lightning storms, winds and snow come from nowhere, unannounced and unpredicted.